Colloquia / Seminars
An overview of the upcoming HEP/HEP Theory seminars can be found at this location: HEP/HEP Theory Seminars. Seminars closely related to the research of our group or invited by our group are given below.
Hannsjorg Weber (Host: Andreas Jung)
Location: Fermilab
Title: Supersymmetry searches in CMS
The standard model (SM) has been extremely successful at describing particle physics phenomena. Nevertheless, it suffers from shortcomings such as the hierarchy problem, the need for finetuned cancellations of large quantum corrections to keep the Higgs boson mass near the electroweak scale, or the lack of candidates for a dark matter candidate. Supersymmetry (SUSY), based on a symmetry between bosons and fermions, is an attractive extension of the SM. A key feature of SUSY is the existence of a superpartner for every SM particle with the same quantum numbers, except for spin, which differs by one half unit. In Rparity conserving SUSY models, supersymmetric particles are created in pairs, and the lightest supersymmetric particle (LSP) is stable and considered to be a candidate for dark matter. SUSY can potentially provide a "natural", that is not finetuned, solution to the hierarchy problem through the cancellation of quadratic divergences in particle and sparticle loop corrections to the Higgs boson mass. The seminar discusses the evolution of searches for supersymmetry performed by the CMS collaboration, including latest techniques used and possible prospects for new search efforts to come.
Date and Time: Tue, 24 Jan 2017, 3:30 PM
Location: Physics Room 242
Moritz Preusser (Host: Andreas Jung)
Location: University of Wien
Title: Top quark mass calibration for MonteCarlo event generators
The lack of knowledge how the top quark mass parameter in MonteCarlo event generators (MCs) is related to field theoretically defined mass schemes limits the theoretical interpretation of the top quark mass measurements based on templates obtained from direct reconstruction analyses at hadron colliders. Since these measurements are the most precise which are available today, clarifying this issue is very important. In the first part of the talk I review the conceptual aspects of the problem and argue which classes of field theoretic heavy quark mass definitions have a close relation to the quark mass parameter in MCs. In the second part I describe a method to calibrate the top quark MC mass parameter by fits of MC hadron level predictions for observables with very strong kinematic mass sensitivity to corresponding hadron level QCD predictions. I demonstrate the approach for 2jettiness in electron positron collisions using factorization based QCD calculations at NNLL + NLO that account for hadronization and the complete top mass dependence, and I present concrete numerical results.
Date and Time: Tue, 23 Aug 2016, 3:30 PM
Location: Physics Room 242
Colloquia/Seminars by Group members

New physics and the top quark at the Large Hadron Collider, A.Jung, Physics Colloquium at Purdue U, 02/18/2016

Top Quark Precision Physics and the Fate of the Universe, A.Jung, Particle physics seminar at BNL, 10/01/2015